Is it the Power Supply, or the Mother Board?

[Harthos1]

Hi guys. My computer won't turn on. Only occasionally. See, I just recently installed a new video capture card, AND replaced one of the video cards. But, when I tried to turn it on after that, it wouldn't turn on. So, I tried taking out the new video card. Then, it turns on OCCASIONALLY. So then, I took out the capture card. No more luck, then.

What the PC does MOST of the time, is flicker. That's why I am thinking it may be the Power Supply

 

[Indigo]

Could be, but it sounds like you may not have had enough ESD protection and could've zapped something when you were installing those items.

I would unplug the system from the outlet, then hold in the power button for about 10 seconds, then let go and let the system sit like that for a bit. Wouldn't hurt to take the CMOS battery out just as an extra step. These aren't guaranteed, but sometimes, being as quirky as they are, can help fix the problem.